Pool Heating Cost Calculator
Monthly cost to heat a swimming pool.
Enter your values
Enter the pool volume in gal.
Enter the degrees to raise/maintain daily loss in °F.
Choose one of: Natural gas ($1.20/therm, 82% eff), Electric heat pump ($0.15/kWh, COP 5), Propane ($2.80/gal, 82% eff).
Enter the days per month heating you are working with.
Results update instantly as you type — no submit needed. Your values are remembered on this device, and the shareable link reopens the calculator with exactly these numbers.
- Estimated monthly heating cost
- $219.69
- Total BTUs needed
- 15,012k BTU
- Fuel type
- Natural gas
Quick answer
Pool heating cost is based on BTUs needed to raise pool temperature, divided by heater efficiency and multiplied by fuel price.
cost = (pool gallons x 8.34 x temp rise x days) / heater efficiency x fuel cost per BTU
At a glance
| What it does | Monthly cost to heat a swimming pool. |
|---|---|
| Category | Home & DIY |
| Inputs needed | Pool volume, Degrees to raise/maintain daily loss, Heater fuel type, Days per month heating |
| Main output | Estimated monthly heating cost |
| Formula | cost = (pool gallons x 8.34 x temp rise x days) / heater efficiency x fuel cost per BTU |
| Cost | Free — no sign-up, no download |
How to use the Pool Heating Cost Calculator
- 1Enter your pool's volume in gallons and how many degrees of heat you need to add or maintain daily.
- 2Choose your heater's fuel type — gas, electric heat pump or propane each have very different running costs.
- 3See the estimated monthly cost based on typical fuel prices and heater efficiency.
Inputs explained
- Pool volume(gal)
- Enter the pool volume in gal.
- Degrees to raise/maintain daily loss(°F)
- Enter the degrees to raise/maintain daily loss in °F.
- Heater fuel type
- Choose one of: Natural gas ($1.20/therm, 82% eff), Electric heat pump ($0.15/kWh, COP 5), Propane ($2.80/gal, 82% eff).
- Days per month heating
- Enter the days per month heating you are working with.
Worked example
Using the values the calculator loads with:
Inputs
- Pool volume20000 gal
- Degrees to raise/maintain daily loss3 °F
- Heater fuel typeNatural gas ($1.20/therm, 82% eff)
- Days per month heating30
Results
- Estimated monthly heating cost$219.69
- Total BTUs needed15,012k BTU
- Fuel typeNatural gas
Frequently asked questions
Which is cheapest to run — gas or heat pump?
Electric heat pumps are usually cheapest to run long-term but heat slower; gas heats fast but costs more per BTU.
Does a pool cover reduce cost?
Yes significantly — a solar or thermal cover can cut heat loss and heating costs by 50-70%.
What do I need to enter into the Pool Heating Cost Calculator?
Just 4 values: pool volume, degrees to raise/maintain daily loss, heater fuel type, days per month heating. Every field starts with a realistic example, so you can change one number at a time and watch the result update instantly.
How does the Pool Heating Cost Calculator work out the answer?
Pool heating cost is based on BTUs needed to raise pool temperature, divided by heater efficiency and multiplied by fuel price. It applies the formula cost = (pool gallons x 8.34 x temp rise x days) / heater efficiency x fuel cost per BTU and shows the working so you can check each step by hand.
Is the Pool Heating Cost Calculator free, and do I need an account?
It is completely free with no sign-up, no download and no usage limit. Everything is calculated in your browser, so the numbers you type never leave your device.
Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.